Multidose hypodermic injector



July 11, 1967 w. P. GABRIELS MULTIDOSE HYPODERMIC INJECTOR Filed Aug. 17, 1964 INVENTOR. WALTER P GABRIELS United States Patent 3,330,277 MULTIDOSE HYPODERMIC INJECTOR Walter P. Gabriels, Harper Woods, Mich, assignor to R. P. Scherer Corporation, Detroit, Mich., a corporation of Michigan Filed Aug. 17, 1964, Ser. No. 389,856 3 Claims. (Cl. 128173) ABSTRACT OF THE DISCLOSURE In a hypodermic injector having a medicament container, a three-way valve in one position permits flow of medicament from the container to the injector and simultaneously free and unrestricted flow of atmospheric air into the container to displace the medicament flowing therefrom. In another position the three way valve permits the medicament to be injected upon operation of the injector and positively closes the interior of the container to atmosphere.

This invention relates to a mnltidose hypodermic injector of the kind shown in Venditty et al. Patent No. 2,928,390, Kath Patent No. 3,123,070 and Gordon application Ser. No. 314,146, filed Oct. 7, 1963.

One object of the present invention is to provide a means for venting air into a medicament container of the injector which means is valve-controlled so as to eliminate the necessity of providing a filter for a vent that is continuously open to atmosphere as in the prior patents and a means for eliminating the possibility of evaporation of the medicament by reason of such valve which positively closes the vent when the device is not in use.

Another object is to provide a 3-way valve of the prior patents mentioned which has an additional porting arrangement for controlling the venting action.

Still another object is to provide a venting port for the valve which is open to atmosphere in a protected crevice of the hypodermic injector provided by a nose piece on the cylinder of the injector having a rear face slightly spaced from the forward face of the injector cylinder.

A further object is to provide the medicament container removably mounted on the cylinder of the injector and a special needle for piercing a closure element of the medicament container which needle has both medicament and venting air passageways therein which communicate with the valve.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my multidose hypodermic injector, whereby the objects above contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in detail on the accompanying drawing, wherein:

FIG. 1 is an enlarged vertical sectional view through the forward end of a multidose hypodermic injector of the kind shown in the above-mentioned patents and application, and includes the valve controlling means of my invention;

FIG. 2 is an enlarged vertical sectional view on the line 2-2 of FIG. 1;

FIG. 3 is a horizontal sectional view on the line 33 of FIG. 2 at the same scale as FIG. 1;

FIG. 4 is a sectional view similar to a portion of FIG. 1 and at the same scale showing the valve in a different position, and

FIG. 5 is an enlarged horizontal sectional view on the line 5-5 of FIG. 2 to show details of a combined medicament and vent tube unit.

On the accompanying drawings I have used the referen-ce numeral 10 to indicate an injector cylinder body and 12 a nose piece mounted thereon. The cylinder body 10 has a bore 14 in which an O-ring equipped plunger 16 is reciprocable, and the nose piece 12 has a discharge orifice 18. A cover member 19 is shown in FIG. 1 which is removed during use of the injector.

A valve plug 20 is rotatable 90 in a valve bore 22 of the cylinder body 10. The valve plug has a T-shaped port, the arms 23 and 24 of which aflFord communication between the cylinder bore 14 and the discharge orifice 18 when the valve plug is in one position as shown in FIG. 1 at which time the arms of the T coincide with valve ports 26 and 28 communicating with the cylinder bore and discharge orifice, respectively. At this time a handle 27 on the valve is against a stop 29 as shown in FIGS. 1 and 3.

When the valve plug 20 is in its other position as shown in FIG. 4, the arm 23 of the T-shaped port communicates with a valve port 30 and the leg 25 of the T communicates with the valve port 26. At this time the handle 27 is against a stop 31 shown dotted in FIG. 1.

A medicament container is shown at 32. It has a resilient closure element 34 seated against a mounting plate 36 secured to the injector cylinder body 10 by screws 38 as shown in FIG. 1. A tube 40 is mounted on the mounting plate 36 and a second tube 42 is telescopically mounted thereon and has a plug 37 in its upper end which carries a bracket 44 terminating in a resilient plug 46 adapted to coact with the upper end of the medicament container 32 as shown in FIG. 1 to retain the container in mounted position on the injector. The plug 37 is pinned to the tube 42 by a pin 39 which also cooperates with a slot 41 in the tube 40 to prevent relative rotation of the tubes 40 and 42. A set screw 43 serves to lock the tube 42 to the tube 40 after the resilient plug 46- is brought into tight contact with the upper end of the medicament container. A knurled knob is provided for manipulating the set screw. This arrangement permits adaptation to a series of different size medicament containers 32 both smaller and larger than the one illustrated.

The prior art above referred to discloses a 3-way valve of the type thus far described and for the purpose of permitting flow of medicament from the container 32 into the cylinder bore 14 as the plunger 16 is retracted (toward the left) therein at a time when the valve is in the position shown in FIG. 4. When it is in the position shown in FIG. 1, forward movement of the plunger 16 under the action of power means such as latch-released expanding springs 48 permits discharge of the medicament through the valve plug 20 and the discharge orifice 18 for hypodermic injection.

My present invention is concerned with a means to vent air into the medicament container 32 under control of the valve plug 20. For this purpose I provide a special type of needle for piercing the closure element 34 comprising a medicament tube 50 and an air tube 52. The air tube is sharpened as indicated at 54 for piercing the closure element 34. The medicament tube has one side cut away as indicated at 56 and its upper marginal end bent toward the tube 52 and secured thereto as by welding indicated at 58 in FIG. 5.

The lower end of the medicament tube 50 communicates with the port 30 as shown in FIGS. 1, 2 and 4 while the lower end of the air tube 52 comunicates with a vent port 60 in the cylinder body 10. The valve plug 20 is provided with an L-shaped port 62-63 which in the position shown in FIG. 4 communicates with both the port 60 and a vent port 64 in the cylinder body 10. The vent port 64 terminates at the forward face 66 of the cylinder body 10 where a crevice is provided in the form of slight space between this face and the rear face 68 of the nose piece 12. The vent port 64 is thus protected from easy clogging as might be the case if the port were exposed on the exterior surface of the injector.

When the valve plug 20 is in the position shown in FIG. 1, the L-shaped port 62-63 while it still communicates with the vent port 60, does not communicate with the vent port 64. Thus theair tube 52 is effectively closed against communication therethrough from atmosphere to the interior of the container 32.

The L-shaped' port 62-63 thus automatically provides a the proper non-venting and venting connections between atmosphere and the interior of the medicament container 32 in the respective position of the valve plug as shown in FIGS. 1 and 4. When in the position of FIG. 1, it is unnecessary and undesirable to have the interior of the medicament container communicating with atmosphere at a time when the injection is being made. This is also true when the hypodermic injector is stored be tween uses at which time the valve may be left in the position of FIG. 1 for avoiding evaporation of the contents of the medicament container.

When the cylinder bore 14 is being filled with medica- *men[ from the container 32 by retraction of the plunger '16 from its forward position close to the valve plug 20 to the position shown in FIG. 1, the valve plug is positioned as in FIG. 4 which automatically vents atmosphere to the interior of the container to permit air to enter for proper displacement of the liquid medicament into the injector cylinder bore 14. Thus, the operations required for refilling and injecting determine the position of the valve plug 20, and my venting arrangement applied to the valve plug permits automatic control of the venting system without further thought on the part of the operator.

The mechanism for accomplishing the venting operations is comparatively simple yet eflicient and efiective and superior to the prior art referred to in that all evaporation and thereby change in the concentration of the medicament is avoided when the medicament container remains mounted on the injector between time-spaced in.- V

jections.

Some changes may be made in the construction and arrangement of the parts of my multidose hypodermic injector without departing from the real spirit and purpose of my invention, and it is my intention to cover by 'my claims any modified forms of structure or use of mechanical equivalents which may reasonably be included within their scope.

I claim as my invention:

1. In a multidose hypodermic injector, a cylinder adapted to receive medicament, a plunger therein operable' in one direction to draw medicament into said cylinder and in the other direction to expel medicament therefrom, a discharge orifice for said cylinder, a 3-way valve between said cylinder and said discharge orifice, a

medicament container communicating with said valve,

said valve in one position thereof establishing communication between said medicament container and said cylinder and in another position thereof establishing communication between said'cylinder and said discharge orifice, and passageway means in said valve to permit free' when the valve is in said one position and is closed to' atmosphere when said valve is in said another-position.

3. A multidose hypodermic injector according to claim 1 whereinv said medicament container is removably mounted on said cylinder and said valve has a needle to pierce'a closure element of said medicament container when mounted on said cylinder, said needle comprises an assembly consisting of a pair of tubes of different di- 7 ameters secured together with one end of the small one sharpened to pierce said closure element and one marginal end of the large one cut away on one side and the other side thereof bent toward and secured to said small one, said cut-away side permitting the entrance to medic- V ament into said larger tube.

References Cited UNITED STATES PATENTS 1,855,373 4/1932 Willumsen 222-484 2,079,587 5/1937 Aronson 128l73 2,839,227 6/1958 Wilson et al. 222484 2,928,390 3/1960 Vendit ty et al 128-173 3,104,448 9/1963 Morrow et al. 128-218 X 3,123,070 3/1964 Kath 128-173 FOREIGN PATENTS 58,945 2/ 1938 Norway.

RICHARD A. GAUDET, Primary Examiner.

ROBERT'E. MORGAN, Examiner. K. L. HOWELL, Assistant Examiner; 

1. IN A MULTIDOSE HYPODERMIC INJECTOR, A CYLINDER ADAPTED TO RECEIVE MEDICAMENT, A PLUNGER THEREIN OPERABLE IN ONE DIRECTION TO DRAW MEDICAMENT INTO SAID CYLINDER AND IN THE OTHER DIRECTION TO EXPEL MEDICAMENT THEREFROM, A DISCHARGE ORIFICE FOR SAID CYLINDER, A 3-WAY VALVE BETWEEN SAID CYLINDER AND SAID DISCHARGE ORIFICE, A MEDICAMENT CONTAINER COMMUNICATING WITH SAID VALVE, SAID VALVE IN ONE POSITION THEREOF ESTABLISHING COMMUNICATION BETWEEN SAID MEDICAMENT CONTAINER AND SAID CYLINDER AND IN ANOTHER POSITION THEREOF ESTABLISHING COMMUNICATION BETWEEN SAID CYLINDER AND SAID DISCHARGE ORIFICE, AND PASSAGEWAY MEANS IN SAID VALVE TO PERMIT FREE AND UNRESTRICTED ENTRY OF ATMOSPHERIC AIR TO SAID MEDICAMENT CONTAINER WHEN SAID VALVE IS IN SAID ONE POSITION AND TO POSITIVELY SEAL SAID MEDICAMENT CONTAINER AGAINST ENTRY OF ATMOSPHERIC AIR WHEN SAID VALVE IS IN SAID ANOTHER POSITION. 